Slide-valve



vUNTTED sTATns PATENT ormon.

RICHARD C. BRISTOL,- OF CHICAGO, ILLINOIS.

SLIDE-VALVE.

Specification of Letters Patent No. 30,611, dated November 13, 1860.

To all whom it may concern.'

Be it known that I, RICHARD C. BRISTOL, of Chicago, in the county of Cook and State of Illinois, have invented certain Improvements` in Slide-Valves; and I do hereby de- Clare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, in which- Figure 1 is a section of a steam chest showing the end of the valve with my improvements attached. Fig. 2 is a cross section of the valve and seat.

Similar letters of reference indicate' like parts in all theA figures.

My present invention relates to, and is an improvement upon the patent granted to me for slide valve dated June 21st 1859 and reissued Feby 7th 1860 and consists, first, in the employment, in combination with a valve su )ported on rolling surfaces, of tracks or caring pieces made separate from the cylinder-tace and lying thereon, and a bearing piece made separate from the valve, and attached thereto in any convenient manner, whereby they may be made of a harder and more durable material, can be re moved and replaced when worn or damaged, without necessitating the removal of either the valve or of the cylinder face, and also admit of adjustmentfor the purpose of carrying the valve with the proper relation to its seat; second, in forming either of such bearing pieces in a wedge shape, and em ploying it in combination with a corresponding incline upon the valve or the cylinder face, so that by moving the same in the direction of its length, the face ot the valve may be adjusted to bring it to a proper bearing on its seat.

To enable others skilled in the art to make and use my invention I will proceed to describe its construction and operation by the aid of the drawing and of the letters of reference marked thereon.

A is the valve chest ot a steam engine, B the cylinder face, in which the ports are cut, represented in the drawing by dotted lines.

C is the valve made in the form repre sented or any other convenient form.

Bearing pieces D of hardened steel or other suitable material are made separate from the valve and are either placed under projecting lips L', as represented, or at tached with their lower edges or sides parallel to the face of the valve by any other Gr, G, are rolls of hardened steel or other V suitable metal, made perfectly true and of the same width of the tracks E. They rest upon E and support the valve by means of the lips C and bearing pieces D.

H, H, are stops cast or atiixed to the sides of the valve C, and serving the purpose of keeping the rollers G, G, in place. The

number and diameter of these rollers are such that they do not fill the space between the stops H, H, by a distance equal to a little more than one half the travel of the valve, so that as the valve traverses the rollers moving at half the velocity of the valve will reach or nearly reach one of the stops H, H, at each stroke, the stops serving to check them and keep them in their proper positions if they tend to become slipped or rolled too 'far in either direction. They are prevented from being displaced in the line of their axes, by the side of the valve chest as shown in Fig. 2.

In order to adjust the valve to a proper bearing on its seat, the bearing pieces D are made in the form of a wedge as represented, and the lip C is made with a corresponding incline. A screw J passes through a proj ection d on the end of D and screws into the body of the valve C, collars i, z', on I at each side of d, hold the lat-ter firmly and cause D to be moved to any required small extent in the direction of its length by the turning of the screw I. A

IVhen the valve is ready to be adjusted it is placed with its face upon the seat with a thin stratum of tallow between, and held firmly there by any sufficient means, and the wedge shaped bearing pieces D, D, are then driven or moved until they find a lirm bearing upon the rollers, so as, to receive the strain on the valve. The shore, bolts, or other means used for holding the valve upon its seat, are now removed, and the several parts are now fully adjusted and in working order. If at any time, from wear or other cause, the valve becomes leaky, or presses too tight-ly on its seat, it may be readily adjusted by means Yof the screws I acting on the Wedge shaped bearing pieces D, D. It

' is evident that the same eect may be produced by making the piece E in a Wedge form with a correspondingly inclined support, and With similar means of adjusting it, but the Way represented I believe to be most convenient.

Having now fully described my invention what I claim as new therein and desire to secure by Letters Patent is 1.`In combination with a valve carried upon rolling supports7 the use of bearingpieces of metal above andbelow such supports, capable of being detached Yfrom the valve and cylinder face, in order Vthat such bearing pieces may be made of a more du- `rable material or be taken out and replaced R. C. BRISTOL.

Witnesses;

N. SNYDER,' G. I-I. BABoooK. 

